Public dissatisfaction with the war, now the nation's longest, has spiked by 7 points just since July. Given its costs vs. its benefits, only 34 percent in the latest ABC News/Washington Post poll say the war's been worth fighting, down by 9 points to a new low, by a sizable margin.

Negative views of the war for the first time are at the level of those recorded for the war in Iraq, whose unpopularity dragged George W. Bush to historic lows in approval across his second term. On average from 2005 through 2009, 60 percent called that war not worth fighting, the same number who say so about Afghanistan now. (It peaked at 66 percent in April 2007.)

As support for the Iraq war went down, approval of Bush's job performance fell in virtual lockstep, a strongly cautionary note for President Obama. Presidents Truman and Johnson also saw their approval ratings drop sharply during the wars in Korea and Vietnam.

The public's increasingly negative assessment comes after a new strategy, including a surge of U.S. and allied forces, led to the Afghanistan war's bloodiest year. According to icasualties.org, nearly 500 U.S. soldiers have been killed and 4,481 wounded in 2010, compared with 317 killed and 2,114 wounded in 2009, and 155 killed, 793 wounded in 2008.

HANDLING IT -- While opposition to the war has grown, Obama himself gets more mixed reviews for handling it. This survey, produced for ABC News by Langer Research Associates, finds that 45 percent approve of Obama's work on Afghanistan, matching his low, while 46 percent disapprove, a scant 2 points from the high. Still, that's considerably better than Bush's ratings for handling Iraq in his second term -- on average, 63 percent disapproved of how he did.

One apparent reason is Obama's pledge to start withdrawing U.S. forces next summer. Fifty-four percent of Americans support that time frame -- up by 15 points since it was announced a year ago. An additional 27 percent say the withdrawal should begin sooner; just 12 percent say it should start later, down 7 points from a year ago.

There are divisions on Afghanistan beyond Obama's approval rating for handling it. Americans split, 48-48 percent, in support for the troop surge he put in place last year -- notably, almost exactly the same division as found in a poll in Afghanistan itself by ABC News, the BBC, ARD German TV and The Washington Post last month.

Americans also divide on whom they trust to handle the situation in Afghanistan: Forty-one percent prefer Obama, while 39 percent choose the Republicans in Congress. That reflects a 6-point drop for Obama since last year, and the first time in his presidency trust has split evenly on this issue. (The decline for the president has occurred disproportionately among Republicans, down 17 points.)

The administration's report today is expected to say the troop surge has led to some progress, particularly in Helmand and Kandahar provinces, but with continued challenges. Similarly, the poll by ABC and its media partners in Afghanistan found sharp gains in Helmand, and spottier ones in Kandahar, but with those advances more than offset by deterioration in other parts of the country.

SECURITY -- Public assessments of the war have turned more negative even though more than half of Americans, 53 percent, say it has contributed to the long-term security of the United States, unchanged from last summer. Far fewer, 22 percent, say the war's contributed a "great deal" toward U.S. security.

It makes a difference: Among people who see a great deal of added security as a result of the war, 63 percent say it's been worth fighting. But among those who say it's contributed, but only somewhat, support for the war falls to 49 percent. And among the four in 10 Americans who say the war has not enhanced U.S. security, or who are unsure, support plummets to 11 percent.

The sharpest decline in views that the war has been worth fighting -- down 14 points since July -- has come among people who also say it's provided a "great deal" of additional security. It may be their sense that no more additional security benefits for the United States can be derived; or that, regardless, the costs no longer justify the gains.

In any case, these results mark the cost/benefit analysis the public employs in evaluating war: Whether the gains, either in security or other measures, are worth the costs, including in terms of lives and dollars. As was the case in Iraq, with casualties up and dollar costs high, the public increasingly is questioning the value proposition of the war in Afghanistan.

GROUP DIFFERENCES -- Republicans have been and remain substantially more supportive of the war, a conundrum for Obama in that the group that most favors the war least likes his handling of it. In any case, views that it's been worth fighting are at new lows across the board.

Half of Republicans now say it's not been worth it, down a dramatic 35 points from the high in 2007. Support drops sharply from there, to 31 percent among independents and a quarter of Democrats, down 27 and 16 points, respectively, from their highs. Views of the war as "worth fighting" are down by 10 or 11 points in all three groups since summer.

Republicans also are more apt than Democrats to think the war has contributed to long-term U.S. security, by a 20-point margin, 70 percent to 50 percent; more likely to support the troop surge, 62 vs. 48 percent; and more apt to say the withdrawal of U.S. forces start later than next summer. But even among Republicans, just 24 percent support a slower start to the withdrawal process.

METHODOLOGY -- This ABC News/Washington Post poll was conducted by telephone Dec. 9-12, 2010, among a random national sample of 1,001 adults, including landline and cell-phone-only respondents. Results for the full sample have a 3.5-point error margin. Click here for a detailed description of sampling error. This survey was produced for ABC News by Langer Research Associates of New York, N.Y, with sampling, data collection and tabulation by TNS of Horsham, Pa.